Liquefied gas lighters



May 27, 1958 c. ZELLWEGER l 2,836,044

LIQUEFIED GAS LIGHTERS Filed July 26, 1956 3 Sheets-Sheet 1 May 27, 1958c. ZELLWEGER 2,836,044

LIQUEFIED GAS LIGHTERS Filed July 26, 1956 5 Sheets-Sheet 3 misil/IIIA-mix 3 United States Patent O LIQUEFIED GAS LlGI-ITERS Conrad Zellweger,Cherie-Bougeries, Switzerland, assigner to La Nationale S. A., Geneva,Switzerland, a corporation of Switzerland Application July 26, 1956,Serial No. 600,336

Claims priority, application Switzerland August 4, 1955 4 Claims. (Cl.67-87) The present invention has for its subject a liqueed gas lighter,wherein the gas is supplied to the burner through j rigid parts havingan orice for the supply of gas to the e' burner, this oriiice beingdisposed opposite to an evaporation zone on said body.

ln known constructions of lighters of this type, the evaporation body isformed by a porous body placed in a cup like seat, between the burnerand the reservoir containing the liquid gas, in such a manner that thelatter is caused to pass therethrough and to evaporate. In this type ofseating, said evaporation body is subjected to a compression so as toadjust the supply of gas to the burner, andV is generally in the form ofa lozenge or diaphragm placed perpendicularly to the passage channel forthe gas and of very large surface area relatively to the cross-sectionalarea of said passage. As a result the evaporation body is compressedover a large area and the larger portion of its mass, through which theliquefied gas is to pass, is compressed. The liquid gas passes throughthis compressed zone whilst being gasied and expanding progressivelyuntil the moment at which it reaches the end of the passage connected tothe burner and which is at atmospheric pressure.

Practice .has shown that it is not possible to obtain a stableadjustment of the delivery of gas to the burner and consequently to theflame, as the evaporation of the liquid gas takes place in thecompressed portion of the porous body and only takes place slowly, sothat the porous body has a zone in which the gas is present partly inthe liquid state and partly in the gaseous state. The positioning of thesaid zone in the porous body varies, on the one hand, in proportion tothe time which has elapsed since the lighter has been opened and, on theother hand, in proportion to the temperature, which is the cause of theinstability of the flame. Under some conditions, said zone is very closeto the mouth of the passage of the burner and it is therefore possiblethat drops of liquid gas may be entrained as far as this mouth, thesudden evaporation of said drops producing momentary increases of thetiame. On the other hand, the gas, when evaporating, deposits waxyresidues which clog the pores of the evaporation body and close, atleast partially, the gas passage, whereby the instability of adjustmentis still further increased. A

Further, in view of the large surface of these diaphragms, relativelylarge forces are necessary for obtaining a regulation of the delivery bycompression, which in general necessitates the use of specialinstruments, such as, for example, a Spanner or screwdriver.

On the other hand it has been found that, when a uniform adjustment ofthe supply of gas to the burner is to be obtained by compression of anevaporation body, it is necessary to define on said latter anon-compressed evaporation zone of small surface area, the supply ofliquid gas to said latter being limited by a short cornpression zone.

According to the present invention this result is obtained by the 'factthat one of the parts compressing the evaporation body is shaped in sucha manner as to create a zone of compression of the evaporation body onlyin proximity to the edge of the evaporation zone, the ow of liquid gasbeing directed transversely with regard to the compressive forcesapplied to said compression zone.

The accompanying drawing illustrates diagrammatically and by way ofexample various constructional embodiments of the invention.

Fig. l shows a portion of a lighter according to the rst form ofconstruction.

Fig. 2 shows a detail of a moditication of this form of construction.

Figs. 3 and 4 relate to two other forms of construction.

Fig. 5 is a section on the line V-V of Fig. 4. Fig. 6 illustrates avariant of the burner according to Fig. 4.

Fig. 7 illustrates, on a larger scale, a part of this burner, the shapeof which has been slightly modied.

The reservoir of the lighter shown in Figure l has an upper Wall 1, alower wall 2 and a side Wall 3. Into the upper wall is screwed a burnerassembly including, among other elements later to be described, a glandnut d which is provided with an internal bore for receiving theexternally threaded portion of a tubular gas escape regulator tube 5through Which the ow of gas is controlled. The iiuidtight seal betweenthe shell 4 and the upper wall l is maintained by a Washer 6, and the4seal between the shell 4 and the tube 5 is maintained by an annularwasher 7 located in a mating groove of the shell 4.

The upper end of the tube 5 is formed as a wheel 12 with a milled edge,enabling the user to screw the tubular gas escape tube 5 more or lessinto the shell 4 and thus to apply an adjustable pressure on anevaporation body formed by a gas feeding element or medium in the formof a lozenge 8 of porous material, clamped between two rigid parts whichare formed respectively by the lower wall 2 of the lighter which servesas a relatively xed anvil and the base of the part 5. Said latter has agasifying chamber 9 for the supply of gas to the burner and is shaped insuch a manner as to create a compression zone of the lozenge 8 only inproximity to the edge of the evaporation zone Which this chamber 9 deneson said lozenge. The gas ilows through the compression Zone transverselywith respect to the compressive forces, before reaching the evaporationzone located opposite of the chamber 9, where it evaporates.

ln the interior of the gas escape regulating tube 5 is located a rod orvalve stem lil of which the lower end has a seal ll which bears againstthe upper edge of the outlet of chamber 9.

The liquid gas soaks the lozenge 8 and evaporates in the zone thereofwhich is located opposite the orifice 9. The lighter is provided with acover 16a which bears against the upper end of the rod or stem l@ whenthe lighter is not being used. As the upper or outer end of the chamber9 is an outlet orilice of very small cross-sectional area as comparedwith the diameter of the mouth of the chamber, it is not necessary toapply any considerable force to the rod 10 for preventing leakages ofgas, in spite of the relatively high pressure thereof in the reservoirof the lighter. When the lighter is operated, the cover lila opens andreleases the rod l0. The latter is raised by the pressure of gas and thelatter can escape to the outside through the passage formed by the spacecomprised between the part 5 and the rod lil. The gas can be igniteddirectly as it passes out through the outer exposed end of the gasregulator tube 5. The height of the ame can be adiusted by turning themilled wheel 12' for modifying the compression of the porcs lozengebetween the parts 2an :l.5.,. A As will-be, seen,the. low.e1:.end4 o thepart. 5 is conical, so that the distance 'separating the Vtwo rigid.partsclamping the Vlozenge.Y 8. istheV minimum along. the -edges ormouthofv the chamber 9. In' this manner is obtained the maximumcompression of the porous lozenge immediately at .theedge of theevaporation zonecreated thereby and the gas expands suddenly,l whichprovides for a satisfactory functioning of the lighter andgreatstability of the llame, even at low temperatures. Further,4 as therareaof the compression zone is small the forcev to beappli'ed to the milledwheel 12is'relatively light, even Vthough a suiciently high specificpressure shouldbe applied to the zone 21. The lower portion of the part18 has an orifice of square cross-section with which engages a key 22of. corresponding shape, secured to a part 23 in the form of a screwhead; said part 23 is held in the wall 2 of the lighter by an elasticring 24. When turning the part 23, the part 18 is screwed into.' the.Vpart 20, whichxenables the pressure applied to the evaporationbodyV 8aby the parts and 17, to be modified'. The operation of this form ofconstruction'. is in all respects similar to that of the of compressionfor ensuringthe regulation of the `delivery of gas.: In the examplesillustrated',the surface of said `Compression zone is vlessthan four.time the cross-sectional whichlit defines v chamber of the gasregulator tube 5a.

dimensions in the form; of anelongated strip or. tape havv ing thecapillary' feeding function of a wick. This element is not presseddirectly against the base 2 by the part 5, butY against a rigidY part1formed by a plate'13 resting von a resilientelement 1 4 `of' rubber,forl example, tted into a recess of-'the lower ,walll 2 of the lighter.In this manner thereis obtained a greater smoothness of adjustment ofthe Vheight of theame byA the milled wheel 12 because the plate'13 tendsto move at the same time as the v part 5, so that! the movement of thelatter is greater than in the case of Fig. I for obtaining the samevariation in`- f pressure on the evaporationfelementu.

Itis known that `liqueiied gases, especially butane, produce, whenevaporating, oily deposits on the evaporation element 'or medium. Thesedeposits finally completely Vobturate the pores of the evaporation body,which prevents correctfunctioning ofthe lighter. In the form ofconstruction shown in Fig. 1 the part 5 may be moved form ofconstruction described with 'referencel to Fig. l, except thatthe'adjustment of thefheight of Vthe ilame is effected by means of the.part 23 instead of by means of the milled wheel 12.

Fig. 4 shows another form; of construction whicha tubular shell orsupport 25. is screwed into the upper wall 1 of the lighter casing.This. support comprises at its lower end a rigid yieldably supportedanvil portion Z6 subjected to the pressure of a spring 27 bearingagainst a screw 28 threaded into the support' 25. The shell has atransverseV medial opening 29 through which the evaporation strip 8apasses and in which itis also clamped' between thev anvil portion 26land the 'mouth ofthe gas In the zone of' the ange 30 there is provideda chamber 9V communieating with an outlet orifice for the supply of gasto the burner. The packing 31 insures fluid'tightness between the shell25 and the iianged part 30. VIn this form of the invention the burnerassembly includes the angedfgas regulator tube 5a `and a gas Vescapesleeve 32 assembledcoaxially. The outer portionY of sleeve 32 ispartially` coupled toanddriven in rotation by a manually manipulatedwheel 12. YThe gas regulator Vtube 5a and sleeve 32 1 f Y havealongitudinal bore whichhouses the valve stem upwardly, by rotation ofthe-milled wheel 12, through a distance suiiicient to eliminate anyappreciable pressure on the evaporation body 8a, so that the gas Vcanpass out of the burner in thev liquid state. whilst producing acleansing of the evaporation zone. VThus, as after'a time offunctioning, the .evaporation body has a tendency to becomegcl'ogged,the. user can clean-'it easily by unscrewing Y the milled wheel 12 solas to allow a small quantity of liquid gas to escape to flush outthe-accumulated residues. Then he should tighten up the Vwheel 12 andeiect adjustment of the height of the ame.

Fig.' 3 shows another form of construction inY which the gas escape tube15 is welded to the upper wall 1 of the lighter. YSaid tube 15 has achamber Q .With an outlet Vo rilice of reduced diameter for theVsupplyrofA gas to the burner and contains a rod 10 having a seal'll andserving the same purpose as the partsy bearing the same references asshown in Pig. 2. However, the rod 10 is urgedV Y l. element Sa isclamped between two rigidY parts formed by the part 15 and by ayieldable -anvilfmember 17fsliding 1n a threaded lpart 18 andsubjectedVto the action of a spring 19. Said part 18`is screwedinto correspondingpart 20 formed integral with the lower wall 2 of the reservoir of thelighter. The fluidtightness between the part 18 and the part 20 isensured by a uidtight joint or rodv 10Y which is subject to ther actionof a spring 16l and forms a valve for the outletlorilice ofthe-chamber9.

TheV edge of the milled wheel 12 has a radially disposed threaded holewhich receives a screw 33 whose inner end'ridesin an annular groove 34(Fig. 5) pro'- videdin the shell 25. Theinner end of screw 33 also formsone part of a stop which determines the maximum adjustedA position ofthe flame by comingint'o contact with one Vor the other faces of anabutment 35. abutment forms a movable stop held in position on the shell25 by `a resilient clamping ring 35a frictionally embracing the bottomof the groove in the ange o f the shell 25'. In this mannenrwhenapplying an additional force onV the wheel 12,-the abutment stop 35 canbeset or reset. Once the abutment is set the turning ofthe wheel V12through an arcdeiined by opposite sides of abutment 35, the distance thetube 5a moves is suicient to permit a normal adjustment of theheight oftheame. On the contrary, when it is desired to scavenge the evaporationzone of the liquid gas feeding element or strip Saby a surge of liquidgas, it is necessary to removev pressure from thestrip by unscrewing thesleeve 32:

through the-manipulation of wheel 12 with a fairly strong etort toproduce a movement of the abutment 35 and lety liquid fuel escapethrough the burner nozzle. Thereafter, the wheel 12 may b e turnedAinthe oppositeI direction to press the mouth of the tubular lgasregulator lagainst the strip and reset the stop 35i to a position Wherethe normal tlameregulating range of movement of the wheel 12 will berestored.

Figi. 6 Villustrates another coustructional form of-a burner assembly,providing for still greater stability'of the flame than thoseV abovedescribed. This Vburner isv This.

T vided with an outlet oriiice of reduced .diameter for supplying gas tothe burner.

A packing 31 insures for gas tightness Vbetween the shell and the gasregulator 5a having a flange. This latter is fitted in a part 12, theupper part of which forms a wheel having a milled edge to enable it tobe easily rotated to screw it into or unscrew it in the shell 25 andthus to permit of adjusting the distance between the part 39 Vand thepart 26, in order to regulate the compression exerted on the evaporationstrip 8a. The parts and l2 are bored longitudinally to receive a rod 1t)subject to the action of a spring 16. The lower end of this rod l0 has auidtight packing 11 adapted to be applied to the orifice 9 to close itwhen the cover, not illustrated, of the lighter, bears on the upperextremity of the rod 1t). vWhen this cover is lifted, the spring 16 actsto move the rod 16 away from the orifice 9 in order to permit of theflow and escape of gas.

The gas inlet chamber 9 to the burner communicates with a chamber 36constituted by a cavity in the part 30. The edge of this cavity isadapted to exert a compression on the evaporation strip 8a around theevaporation zone which is disposed inside the augmented chamber 36. rlheheight of this latter is substantially equal to the thickness of theevaporation strip 8a when it is not compressed. In this way, when theparts 26 and 30 are moved together to the maximum extent in order thatthe annular edge 37 of the chamber 36 exerts a very strong compressionon the evaporation strip 8a, the part of this body 8a which is disposedin the chamber 36 undergoes practically no compression.

When the lighter is closed, the chamber 36, the volume of which isalmost completely occupied by the evapora tion body Sa in thenon-compressed state, can be filled with gas in the liquid state. Whenthe lighter is opened the quantity of liquid gas does not evaporateinstantaneously, but slowly, because the -gas is retained Iby the fibresof 'the evaporation body, so that on ignition a stable llame is obtainedat temperatures lower than 15 C. `It will -be noticed in addition, thatthe evaporation or gasifying chamber 9 is in the form of a truncatedcone which is of advantage because if a little gas in the liquid stateis disposed in the passage the liquid drop has a tendency to occupy aminimum surface by reason of capillary action rand moves towards thepart of minimum section of the cone whence it is expelled by the gaseousow.

It may be observed that butane gas which is currently used for lightersoperating with liquilied gas, contains sometimes very small fractions ofa hydrocarbon having a higher boiling point than that of butane andthese fractions have a tendency to accumulate in the evaporation zone inthe form of a liquid droplet Fig. 7 illustrates a variant of the part 30in which the chamber 9 is cylindrical, whereas the upper wall of theentrance chamber 36a is flat instead of having the shape of a truncatedcone, as illustrated in Fig. l. It may be observed that the height ofthis entrance chamber 36a is smaller than that of the chamber accordingto Fig. 1. In practice it is not necessary that the part of theevaporation body, which is located in this chamber, be completelyuncompressed. It is sullicient in practice that the compression of theevaporation body in the chamber 36 or 36a be much less than that exertedon this body by the annular edge 37. lIn practice it is of advantage tomake the height of the chamber greater than one half the thickness ofthe evaporation body in the uncompressed state, but less than thisthickness. However, acceptable results can still be obtained when theheight of this chamber is greater than the thickness of the evaporationbody in the uncompressed state. Notwithstanding, this height should notexceed twice the thickness of the evaporation body, because without thisa substantial part of the volume of the chamber 36 is not occupied bythe evaporation body and since the gas can accumulate there in theliquid state, there is produced again, at the time of openf6 ing thelighter, a sudden evaporation of this gas which produces a considerablelowering of the temperature of the part 30, which involves the danger ofagain producing the irregularities in the llame which it is sought toavoid. vIn the embodiment described in Fig. 6, the chamber 36 is formedin the part 30 in which is provided the orifice 9 for the supply of thegas to the burner, but it is to be understood that this chamber couldalso be provided in the part 26, the part 30 then having only the orice9, which would come directly into contact with the evaporation body 8a.As a variant, a cavity could also be provided in each of the parts 30and 26, these cavities being disposed opposite to each other in such away as together to form the chamber 36.

In all the constructional forms described, one of the rigid parts has acircular edge for electing the compression of the evaporation body, butgood results can also be obtained lby clamping the evaporation bodybetween plane surfaces of the rigid parts, on condition that thecompression zone is produced only in proximity to the edge of theevaporation zone.

I claim:

l. A liquefied gas fueled lighter of the character described, comprisinga casing having a reservoir therein constructed to receive liquefied gasfuel, a burner structure `carried by said casing and having therewith afuel conducting passage leading outwardly to the mouth of the burner, aporous fuel conducting body having one portion thereof which lies acrossthe inner end of such passage to provide a fuel evaporation zone at thesurface of such portion which faces said passage, clamping meansincluding opposed members compressing between them portions of said bodywhich surround said evaporation zone to provide a compression zonesurrounding said evaporation zone, said porous body also having portionswhich are disposed on the periphera'lly outward side of said compressionzone and which are exposed to said reservoir to provide a liquid fuelconducting zone surrounding said compression zone, whereby liquid fuelpassing from said reservoir to said evaporation zone enters said bodythrough said portions which are exposed to said reservoir on theperipherally outward side of said compression zone, and then passesthrough said compression zone to said evaporation zone in paths of owwhich are transverse to the compressive forces applied by said clampingmembers, said clamping means being adjustable to regulate saidcompressive forces and thereby alter the rate of llow of fuel throughsaid compression zone to said evaporation zone.

2.. A liquefied gas fueled lighter of the character described,comprising a casing having a reservoir therein constructed to receiveliquefied gas fuel, a burner structure including a hollow housingmounted in a wall of said casing and extending into said reservoir, saidhousing having therewithin a fuel conducting passage leading to themouth of the burner, the portion of said housing within said reservoirhaving a side wall provided with an opening which aords communicationbetween said reservoir and the interior of said housing, a strip ofporous fuel conducting material having one portion thereof which liesacross the inner end of such passage to provide a fuel evaporation zoneat the surface portion of such strip which faces said passage, saidstrip also having portions which extend from the interior of saidhousing and outwardly through said opening into the space within saidfuel reservoir, a clamping member within said housing which engages theportions of said strip which surround said evaporation zone, to providea compression zone surrounding said evaporation zone, a second clampingmember also disposed interiorly of said housing and which engages thesurface of said fuel conducting strip which is juxtaposed to saidevaporation zone and said compression zone, and means affording relativeadjustment of said clamping members one toward and from the other, toalter the compressive forces appliel'by V.Said:clampingmembers',totheportions .of the' fuel 'Leonduting stripY which :surround `suchevaporation :zonegtlreaforesaid portionsrof said'istrip affordingra'fuelconducting Zone through ,said strip Which lsurroundssaidV'compressionzonewl1ereby, Viiquid vfuel passing from said reservoir-to-sa'i'd 4evaporation zone enters said Astrip. from the portionsthereof Which' `are Vdisposed Von the peripherally outward side of saidcompressionzone and' then passes throughsa'id `wmpr'ession'zone to saidevaporation fzone in paths of yow which ,areV transverse to thecompressive Yfoiees applied by saidY clamping members.

35A liqued gas' fueled lighter of the'r'charact'er described vaccordingEto clairrr2,l Wherein,th'e housing 'is fixed in the casing and themeans vaffording relative ad-y justment. of said clamping members fonefrom and to,-

Y 7.4. A1 liquefied gas. fueled lighterV of Vthe .character der, scribedaccording to claim 3, wherein the abutment-,is f rictionally clamped ,tothe housing, whereby, an angular force onthe abutment in excess of thenormal forc :to regulate the movementof said inner tubular elementztoproduce the selectedV gasdschargepressure Willeause Y theelementltorrelieve the strip of V.compression 'sufficiente ly tofperniita-,cleansng surge of liquid gas to pass ,i through the inner tubularelement and out past the tip of the valve stem. Y Y

References Cited in the file of this patent UNITED STATES PATENTS

